I have two problems with this.
1.After life is a product of belief and religion. The question is invalid to begin with, let alone the idea of trying to provide scientific proof for a product of belief.
Human species have created gods, myths, legends and so religions to survive. Almost all of these belief systems are based on the idea that they are special life forms, because their level of consciousness differ from all other species on the planet. So there must be something seperate, special and above everything about their consciousness. Which is defined as a 'soul' in general and the belief that it must be immortal. Simply put, 'I ache, I feel pain, I get sick and I die. I refuse that I will perish without anything left, there must be something precious and unique in me that is going to live forever.' This invention has lots of 'benefits' for the individual and the society from a primitive point of understanding. It's about control and also serves as a coping mechanism with death and pain; being mortal, if you will.
So the understanding of 'consciousness' here not the consciousness but the most ancient concept of soul. It's just not fashionable any more to name this way I guess. Because then it doesn't sound 'scientific'? LOL Not to mention, if you use the word 'soul' the target audience is going to change. It's 'out' you see.
2. When we say 'near death experience', we are talking about an organism facing its absolute fear. All of our fears are based on fear of death. This is so strong, it can actually kill the organism by shock. I don't get how people actually think anything felt, percieved in an extreme circumstance can count as reliable experiences, let alone proof. When we are drunk, lol even tipsy we should question what we feel.
I am sure you guys are familiar with the phrase 'what the dog sees'. When we are extremely scared, the panick and shock we experience turns us into the most dumb animal, trying to get out that situation at all cost, not some sensitive, highly aware and conscious agent recording his emotions and thoughts.
Looking for proof for after life, requires the belief in soul, and it is looking for the soul. And it makes good money, that's all.